/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.http.client;

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpConnectionManager;
import org.apache.commons.httpclient.HttpMethodBase;
import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager;
import org.apache.commons.httpclient.methods.*;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.http.HttpMethod;
import org.springframework.util.Assert;

import java.io.IOException;
import java.net.URI;

/**
 * {@link org.springframework.http.client.ClientHttpRequestFactory} implementation that uses
 * <a href="http://jakarta.apache.org/commons/httpclient">Jakarta Commons HttpClient</a> to create requests.
 *
 * <p>Allows to use a pre-configured {@link HttpClient} instance -
 * potentially with authentication, HTTP connection pooling, etc.
 *
 * @author Arjen Poutsma
 * @see org.springframework.http.client.SimpleClientHttpRequestFactory
 * @since 3.0
 * @deprecated In favor of {@link HttpComponentsClientHttpRequestFactory}
 */
@Deprecated
public class CommonsClientHttpRequestFactory implements ClientHttpRequestFactory, DisposableBean {

    private static final int DEFAULT_READ_TIMEOUT_MILLISECONDS = (60 * 1000);

    private HttpClient httpClient;


    /**
     * Create a new instance of the {@code CommonsHttpRequestFactory} with a default
     * {@link HttpClient} that uses a default {@link MultiThreadedHttpConnectionManager}.
     */
    public CommonsClientHttpRequestFactory() {
        this.httpClient = new HttpClient(new MultiThreadedHttpConnectionManager());
        this.setReadTimeout(DEFAULT_READ_TIMEOUT_MILLISECONDS);
    }

    /**
     * Create a new instance of the {@code CommonsHttpRequestFactory} with the given
     * {@link HttpClient} instance.
     *
     * @param httpClient the HttpClient instance to use for this factory
     */
    public CommonsClientHttpRequestFactory(HttpClient httpClient) {
        Assert.notNull(httpClient, "httpClient must not be null");
        this.httpClient = httpClient;
    }


    /**
     * Set the {@code HttpClient} used by this factory.
     */
    public void setHttpClient(HttpClient httpClient) {
        this.httpClient = httpClient;
    }

    /**
     * Return the {@code HttpClient} used by this factory.
     */
    public HttpClient getHttpClient() {
        return this.httpClient;
    }

    /**
     * Set the connection timeout for the underlying HttpClient.
     * A timeout value of 0 specifies an infinite timeout.
     *
     * @param timeout the timeout value in milliseconds
     * @see org.apache.commons.httpclient.params.HttpConnectionManagerParams#setConnectionTimeout(int)
     */
    public void setConnectTimeout(int timeout) {
        Assert.isTrue(timeout >= 0, "Timeout must be a non-negative value");
        this.httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(timeout);
    }

    /**
     * Set the socket read timeout for the underlying HttpClient.
     * A timeout value of 0 specifies an infinite timeout.
     *
     * @param timeout the timeout value in milliseconds
     * @see org.apache.commons.httpclient.params.HttpConnectionManagerParams#setSoTimeout(int)
     */
    public void setReadTimeout(int timeout) {
        Assert.isTrue(timeout >= 0, "Timeout must be a non-negative value");
        getHttpClient().getHttpConnectionManager().getParams().setSoTimeout(timeout);
    }


    public ClientHttpRequest createRequest(URI uri, HttpMethod httpMethod) throws IOException {
        HttpMethodBase commonsHttpMethod = createCommonsHttpMethod(httpMethod, uri.toString());
        postProcessCommonsHttpMethod(commonsHttpMethod);
        return new CommonsClientHttpRequest(getHttpClient(), commonsHttpMethod);
    }

    /**
     * Create a Commons HttpMethodBase object for the given HTTP method
     * and URI specification.
     *
     * @param httpMethod the HTTP method
     * @param uri        the URI
     * @return the Commons HttpMethodBase object
     */
    protected HttpMethodBase createCommonsHttpMethod(HttpMethod httpMethod, String uri) {
        switch (httpMethod) {
            case GET:
                return new GetMethod(uri);
            case DELETE:
                return new DeleteMethod(uri);
            case HEAD:
                return new HeadMethod(uri);
            case OPTIONS:
                return new OptionsMethod(uri);
            case POST:
                return new PostMethod(uri);
            case PUT:
                return new PutMethod(uri);
            case TRACE:
                return new TraceMethod(uri);
            case PATCH:
                throw new IllegalArgumentException(
                        "HTTP method PATCH not available before Apache HttpComponents HttpClient 4.2");
            default:
                throw new IllegalArgumentException("Invalid HTTP method: " + httpMethod);
        }
    }

    /**
     * Template method that allows for manipulating the {@link org.apache.commons.httpclient.HttpMethodBase}
     * before it is returned as part of a {@link CommonsClientHttpRequest}.
     * <p>The default implementation is empty.
     *
     * @param httpMethod the Commons HTTP method object to process
     */
    protected void postProcessCommonsHttpMethod(HttpMethodBase httpMethod) {
    }

    /**
     * Shutdown hook that closes the underlying {@link HttpConnectionManager}'s
     * connection pool, if any.
     */
    public void destroy() {
        HttpConnectionManager connectionManager = getHttpClient().getHttpConnectionManager();
        if (connectionManager instanceof MultiThreadedHttpConnectionManager) {
            ((MultiThreadedHttpConnectionManager) connectionManager).shutdown();
        }
    }

}
